Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Exam VI - Respiratory & Genital Infections > Flashcards

Exam VI - Respiratory & Genital Infections Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Pharyngitis

A 
Streptococcus pyogenes
Group A beta-hemolytic strep, GAbS
Transmission: Respiratory droplets 
Incubation 2-4 days
Symptoms: Abrupt onset fever, sore throat with exudate (suppurative = pus generating), may have abdominal pain, nausea, vomiting
Diagnosis: rapid strep test
At risk population: children
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Streptococcus pyogenes

A

Gram-positive cocci in pairs or chains
Catalase negative
Beta-hemolytic on blood agar plate
M Protein: antiphagocytic and antigenic variation
SPE: Streptococcal pyrogenic exotoxins; encoded by phage with many enzymes; pyro = fever causing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Scarlet Fever

A

caused by streptococcus pyogenes
Potential complication of strep throat due to pyrogenic exotoxin with symptoms 1-2 days after pharyngitis
Sandpaper rash
Starts on face spreads to body, not on palms or soles
1 week duration then desquamation
Strawberry tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Rheumatic Fever

A

caused by streptococcus pyogenes
Potential complication of strep throat
Antibodies made against the S. pyogenes M protein (during original pharyngitis infection) cross react with
protein on heart valves and joints
Damage heart valves over time causing endocarditis leading to scarring of heart valves, stenosis, regurgitation, and rheumatic heart disease (RHD)
Polyarthritis - multiple joints affected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Corynebacterium diphtheria

A

Gram positive, club shaped (rod), non-motile
Catalase positive
Humans are the only reservoir
Respiratory: transmission respiratory aerosols
Cutaneous: transmission skin contact

Virulence Factor
Diphtheria toxin: phage mediated produced at site of infection that disseminates through the blood and binds to receptors on heart, throat, and nerve cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Mechanism of Action: diphtheria

A

Same as P. aeruginosa Exotoxin A (AB toxin)
ADP-ribosyl transferase
Inactivates elongation factor 2
Inhibits host protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Respiratory diphtheria

A

Incubation 2-4 days
Attach and multiply in the pharynx- location of infection
Exotoxin causes tissue damage
Formation of thick gray pseudomembrane exudate - will bleed if tested with swab
Malaise, sore throat, fever, exudative pharyngitis, bill neck
Potential complications: myocarditis and neurotoxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Cutaneous diphtheria

A

Gains entry to subcutaneous tissue through break in the skin - immunocompromised
Chronic, non-healing ulcer - necrosis due to toxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Diagnosis of diphtheria

A

Selective agar: cysteine tellurite blood agar
Tinsdale agar
Tellurite: grayish black colonies
Cysteine: brown halos surrounding colonies
PCR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Bordetella pertussis

A

Gram negative (has LPS) coccobacillus (rod), aerobic
Disease: pertussis
highly contagious disease with uncontrolled violent coughing
High Risk Population: unvaccinated children and vaccinated teens (middle school, high school age)

Virulence factors:
Attachment: bind to ciliated epithelial cells = pertactin and filamentous hemagglutinin
Tissue damage caused by pertussis toxin
ADP ribosylating activity of G proteins, increased cAMP, increased resp. mucus
tracheal cytotoxin has a high affinity for cilia causing ciliostasis or death of cells leading to characteristic cough; also stimulates IL-1 resulting in fever via T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Pathogenesis of Bordetella pertussis (4)

A
  1. Exposure: aerosol droplet inhalation
    needs human reservoir
  2. Attachment to ciliated epithelial cells via pertactin and filamentous hemagglutinin
  3. Proliferation
  4. Tissue damage via pertussis toxin and tracheal cytotoxin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Pertussis: 3 stages

A

7 to 14 day incubation

  1. Catarrhal: coldlike symptoms, runny nose, sneezing, malaise, low fever, loss of appetite; highly transmissible, large # of bacteria
  2. Paroxysmal: damage ciliated cells, impaired mucus clearance; prolonged coughing fits with inspiratory whoop, 40-50/day, vomiting exhaustion, ruptured blood vessels in the eyes
  3. Convalescence: recovery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Diagnosis of Pertussis

A 
Nasopharyngeal aspirate best
Classic: Bordet-Gengou medium
Current: Regan-Lowe agar 
Inoculate at bedside
7-12 days incubation
PCR – best if available
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Treatment of Pertussis, Tetanus, and Diphtheria

A

Acellular Vaccine - currently recommended
Inactivated pertussis toxin + Filamentous hemagglutinin + pertactin
Part of DTaP for children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Pneumonia

A

Inflammation of the lungs accompanied by fluid filled alveoli and bronchioles
May involve: hemoptysis (coughing blood)
Caused by inhalation of aerosols, aspiration of normal flora (URT and GI), or hematogenous spread from another site of infection
nosocomial or community acquired
Types: typical vs. atypical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Typical Pneumonia

A

streptococcus pneumonia
Abrupt onset, fever, chills, congestion, shortness of breath (dyspnea), chest pain
**Productive cough
Streptococcus pneumoniae, Klebsiella pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus

Characteristics of bacteria: also known as pneumococcus, lobar pneumonia, gram positive, pairs or chains, alpha hemolytic, blood agar, CAPSULE, adhesin, IgA protease, pneumolysin: lyses ciliated epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Typical Pneumonia: Causes, Dx, and Tx

A

Fall & winter, CAP (community acquired pneumonia)
Predisposing factors: viral infection, influenza, HIV, alcoholism, children, elderly, splenectomy

Diagnosis: sputum sample - rust colored
Microscopy - gram positive cocci and numerous PMNs, antigen agglutination (secreted in urine as well as sputum)
Alpha hemolysis
Optochin sensitive

Vaccines:
Pneumovax: 23 most common capsule serotypes, PPSV23; adult
Pneumococcal conjugate vaccine: PCV13, children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Atypical Pneumonia

A

Organisms not seen with Gram stain (except Lp)
fever, headache, malaise, myalgia, nausea, diarrhea, many neutrophils, dry hacking cough
***Nonproductive cough (no sputum)

Mycoplasma pneumoniae
Chlamydophila spp.
Legionella pneumophila
Coxiella burnetii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Mycoplasma pneumoniae

A

Primary atypical pneumonia, community acquired
Symptoms: atypical pneumonia; persistent nonproductive cough, excessive sweating
May last several weeks to months; lack of seasonality
“walking pneumonia”
Characteristics: smallest free living microbe, no cell wall, capsule, adhesin (attachment to the base of the cilia)
Transmission: inhalation of aerosols

Dx: usually can not see the bacteria with microscopy, large number of PMNs, grows very slowly in culture, 2-6 weeks, cold agglutinins
PCR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Chlamydophila pneumonias

A

Characteristics: gram negative, CAP, obligate intracellular bacteria; mild infection
TWAR: Taiwan Acute Respiratory Agent
Transmission: respiratory droplets
Symptoms: mild fever, sore throat, malaise, persistent cough; atypical pneumonia

Diagnostics: Microscopy/Gram stain: no organisms seen
large number of PMNs
ELISA
Elementary body: body that gains entry to the cell and survive; most active
Reticulate body: when ready to multiply it starts the second stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Psittacosis

A

Chlamydophila psittaci
Parrot fever
Disease of birds can be transmitted to humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Legionnaires’ Disease

A

Legionella pneumophila; atypical pneumonia
Characteristics: gram negative, does not Gram stain well, intracellular
Water cooling towers and air conditioning units
Environment: amoeba
Human: alveolar macrophages
Transmission: inhalation of aerosolized droplets
Symptoms: abrupt onset of fever, headache, pleurisy, chills, myalgia, dry cough; complications involving GI tract, CNS, liver and kidneys are common
Pontiac Fever: strong immune system means that this infection will probably go away on its own

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Legionnaires’ Disease: Risk and Dx

A

Risk factors: smokers, COPD, high alcohol consumption, elderly, immunosuppressed, renal transplant patients, or patients on dialysis

Diagnosis:
Culture: fastidious (picky) - buffered charcoal yeast extract agar (BYCE) with iron salts and cysteine
Fluorescent antibody staining
Antigen can be detected in urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Common Causes of Nosocomial Pneumonia

A

Pseudomonas aeruginosa, S. aureus, H. influenza
Enterics: Enterobacter , Klebsiella, E. coli, Serratia marcescens - if they go anywhere else other than GI via vomiting = problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Pseudomonas aeruginosa

A

Gram-negative rod, ubiquitous, capable of growing on many substrates and temperatures ranging 4-42 C, aerobic, and forms a biofilm - Alginate capsule
Motile: flagella and pili
Opportunistic and nosocomial infections; highly antibiotic resistant
Characteristic color and sweet grape like odor
Oxidase positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

P. aeruginosa: CF

A

Risk factors: cystic fibrosis - colonized by S. aureus first then with P.aeruginosa by 5 yrs old - lifelong
Burkholderia cepacia is also another lung bacteria that affects those with CF
These bacteria cause the immune system to cause the damage (indirectly)
Most CF patients die from P. aeruginosa lung associated infections (90%)
Research very hard because alginate in P. aeruginosa contributes to the biofilm formation
Fresh isolates of P. aeruginosa from CF patients are mucoidy, but in vivo and in vitro switching in the mucoidy phenotype via quorum sensing in culture
Hospitalized on ventilation- high risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Anaerobes

A

Aspiration of respiratory or gastric material
Risk factors: dental work and loss of consciousness
mixture of Bacteroides and Fusobacterium - necrotizing, lung abscesses, empyema (formation of pus in pleural cavity)
***copious amounts of foul smelling sputum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Potential Bioterrorism Agents

A 
Anthrax
Plague
Q fever
Tularemia
Brucellosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Bacillus anthracis

A

Gram positive rods occurring in chains
Aerobic, non-motile, forms resistant endospores
Spores remain viable for years in soil, dried or processed hides; present in air, water, soil and vegetation
Three types: cutaneous, inhalation, and GI

Inhalation: capsule (polyglutamic acid capsule (AA)) + anthrax toxin
Transmission: inhalation of endospores (spores have no taste or smell)
Symptoms:
Initial - sore throat, mild fever, myalgia, cough
After several days - severe coughing, nausea/vomiting, lethargy, confusion, shock, death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Anthrax Toxin

A

Major virulence factor secreted by B. anthracis
Encoded by plasmid pXO1 carrying three toxin genes
A/B toxin
Three component proteins:
Protective antigen (PA)
Edema factor (EF)
Lethal factor (LF)
*these cause tissue damage, edema, and cell death
High mortality rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Anthrax Vaccine

A

Diagnosis: microscopy/Gram stain of sputum
Treatment: penicillin, doxycycline, ciprofloxacin
Vaccine available for military and researchers
decontamination is costly and time consuming

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Mycobacterium tuberculosis: General Information

A

Aerobic, acid fast rods, intracellular
Cell wall contains mycolic acid, which areresistant to detergents and common antibiotics and provide protection from desiccation
Grows very slowly on culture
Due to the high lipid content of the cell walls acid-fast bacteria retain the carbolfuchsin and will appear fuchsia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

TB: Transmission, Symptoms, Risk Factors, and Virulence

A

Transmission: inhalation
Incubation: 4-12 weeks
Virulence: cord factor (not a toxin) causing a characteristic serpentine arrangement due to aggregation of the cells
Tissue necrosis is due to immune response (indirect)
Symptoms: productive cough (sputum may be bloody), mild fever, fatigue, malaise, weight loss, sweating
Risk factors: poor nutrition, drug users, alcoholics, crowded living conditions (prisons), immunocompromised
Endemic areas: Southeast Asia, Sub-Saharan Africa, Eastern Europe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Three types of Tuberculosis

A
  1. Primary tuberculosis – initial case of tuberculosis disease
  2. Secondary tuberculosis – reactivated tuberculosis
  3. Disseminated tuberculosis – tuberculosis involving multiple systems (poor prognosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Mechanism of TB

A

Inhalation of bacteria and then engulfed by alveolar macrophages, but not killed (intracellular)
Survive and multiply and attract and activate more macrophages to form tubercle/granulomas to hide from immune system
Can remain dormant for years to decades, but immunosuppressed individuals become infected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Change in TB Over Time

A
  1. Caseous lesion- cheese-like consistency
  2. Ghon complexes -calcified caseous lesion; show up prominently in chest X-rays (in lungs and lymph nodes)
  3. Tuberculous cavities- tubercle that has liquefied and formed an air-filled cavity from which bacteria can spread
    (reactivation and miliary tuberculosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

TB Dx

A

Screening: tuberculin skin test, Mantoux test, PPD test (same thing just different names)
Intradermal injection of purified protein derivative, then check site in 48-72 hours
CMI - cell mediated immunity
Positive indicates exposure not an active infection, so must get a chest X-ray to look for signs of tubercles
Microscopy sputum, acid fast stain, fluorescent auramine stain, Lowenstein-Jensen agar
Grows very slowly -6-8 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

TB Resistant Strains and Tx

A

MDR-TB: multidrug resistant - resistant to isoniazid and rifampin
XDR-TB: extremely drug resistant- resistant to isoniazid, rifampin, and at least one of the 2nd line drugs
DOTS: Directly Observed Treatment Short course
recommended by the WHO and CDC; ensures patient compliance or jail

Treatment: combination therapy of isoniazid and rifampin or ethambutol and pyramindole (RIPE)
6-9 months
Potential exposure: isoniazid treatment
BCG Vaccine: Bacille Calmette-Guerin
Live, attenuated M. bovis
not used in the U.S. because screening would not be as cheap as it is now and anyone with suspected TB would need a chest X-ray and other tests

39
Q

Lactobacillus sp.

A

Facultative or strict anaerobic gram positive rod
NF of mouth, stomach, GI track, GU tract
Can cause opportunistic infections

40
Q

Bacterial Vaginosis (BV)

A
  1. Discharge – watery /milky adherence to the vaginal wall
  2. pH – raised
  3. Specific tests – Amine test: KOH + vaginal fluid; fishy odor =“Whiff test”; BV – Positive Amine Test
  4. Gram stain results – clue cell; gram variable

Clue cell: overgrowth of bacteria present; gram negatives and positives; epithelial cells is covered with growth
No itchiness, no painful urination; not a lot of discomfort
There are no white cells (PMNs); neutrophils; aka your body is not reacting to it and your immune system isn’t activated
Very bad odor and vaginal discharge due to putrescine, cadaverine, trimethylamine (product of bacterial metabolism)

41
Q

BV Causative Agents

A

Gardnerella vaginalis – most associated
Mycoplasmas
Anaerobes – Peptostreptococci, Bacteroides spp., and Mobiluncus spp.

42
Q

Garnerella vaginalis

A 
causative agent of BV
Gram-variable bacillus
Member of endogenous vaginal flora
Major organism associated with BV
Culture not really very useful for dxs
Seen on gram stain – clue cells
Gardnerella has been isolated from sexually inexperienced girls
A disturbance of the vaginal microbial ecosystem
43
Q

Mycoplasma

A

causative agent of BV
Gram stain: no gram stain because no cell wall
Cell membrane characteristic: has sterols
Why are these characteristics important: cannot treat it with beta lactams because they target the cell wall, which is does not have

Other Members of Species:
M. genitalium: non-gonococcal urethritis (NGU) and Pelvic Inflammatory Diseases (PID)
Ureaplasma urealyticum: NGU, pyelonephritis, spontaneous abortion
M. hominis: Pyelonephritis and postpartum fevers

44
Q

Mobiluncus species

A

causative agent of BV
Obligate anaerobic gram variable curved rod with tapered ends
Classified as gram positives: have gram-positive thick cell wall, lack endotoxin, and is susceptible to vancomycin, etc.; doesn’t stain well

Mobiluncus curtisii
Abundant in women with BV
Role in pathogenesis vague

45
Q

Streptococcus agalactiae

A

Gram positive cocci in chains
Beta hemolytic; small zone of hemolysis compared to strep pyogenes
Lancefield: group B
Capsule: polysaccharide and antibody protective
Vaginal colonization: causes bladder infections, premature delivery, prolonged membrane rupture, and postpartum fever
Transmitted to infants during birth leading to neonatal disease
Can cause neonatal meningitis if capsule present

46
Q

Neonatal Disease: Streptococcus agalactiae

A 
Early onset (<7 days old): bacteremia, pneumonia, meningitis, severe consequences
Late onset (1 week to 3 mos.): bacteremia with meningitis if capsule present
47
Q

Vulvovaginal candidiasis(VVC)

A

Second most common vaginal infection in US
primary source - endogenous
opportunistic pathogens (when taking antibiotics and normal flora decreases allowing its population to grow)
Fungal Species: Candida albicans and Candida spp.

Three groups of females
1. never had an episode
2. infrequent, isolated episodes
3. repeated, recurrent, chronic infections
75% of women will have at least one episode
some are more prone than others

48
Q

Candida Characteristics

A
  1. Discharge - Cottage cheese appearance, discrete pustulopapular lesions
  2. pH – 4.5
  3. Specific tests – germ tubes from yeast; grows on Sarbouraud Dextrose agar
  4. Gram stain results - positive
49
Q

VVC Symptoms, Dx, and Tx

A

chief complaint - itching
burning sensation when urinating
cervix normal
erythema, swelling of labia and vulva

Dx: microscopic finding - yeast cells, budding hyphae, few PMN’s (neutrophils)
laboratory identification
**germ tubes for Candida albicans
pseudohyphae on cornmeal agar
biochemical tests for other species
Grows on routine lab media, but to culture would use ***Sabouraud dextrose agar

Tx: hard to treat because they are eukaryotic

50
Q

Other Candida Infection Symptoms

A 
Esophagitis – HIV/immunocompromised
Diaper rash – infants and elderly
Thrush – HIV/immunocompromised
Nail infections – occupation with hands in water like dishwashers/artificial nails
Systemic - immunocompromised
51
Q

Trichomoniasis

A

anaerobic flagellated protozoan: life cycle is simplest for protozoa; binary fission, no cyst stage
requires preformed purines, pyrimidines, fatty acids, and sterols
Survives on fomites for approx. 30 minutes - needs human host

  1. Discharge - frothy yellowish, green; large amount of discharge
  2. pH – 4.7
  3. Specific tests – wet prep, see protozoan; large number of PMNs; positive whiff test
  4. Gram stain - will NOT show up on a gram stain because not bacteria
52
Q

Trichomoniasis: At Risk

A

At risk: lower socioeconomic populations, multiple sexual partners, previous history of STD, coexistent infection, non-use of barrier or hormonal contraceptives

53
Q

Trichomoniasis: Signs and Symptoms

A

Vaginitis, urethritis
Chief complaint – frothy yellowish, green discharge
Strawberry cervix - localized hemorrhages on cervix and vagina (dark spots)

Other signs/symptoms: bad odor, vulvar pruritus (itching), dysuria (painful urination)
Vaginal soreness, dyspareunia (pain during sex)
Males - slight urethral discharge

control depends on treating partners: evaluate for other STD’s and evaluate for candidiasis, BV

54
Q

Cervicitis and Urethritis in Females

A

Cervicitis: most common STD syndrome
Often “Silent partner” to male urethritis
Inflammation of columnar and subepithelium of endocervix is greatest in adolescent girls so they are very susceptible compared to older women

Cervicitis and Urethritis: up to 70% of women are asymptomatic
Serves as reservoir
Dysuria, vaginal discharge, vaginal pruritus (itching and discharge)
Mucopurulent watery discharge
Easily induced bleeding of the cervix

55
Q

Neisseria species

A

Neisseria gonorrhoeae- pathogenic
Neisseria meningitides - pathogenic
Neisseria species- normal flora and non-pathogenic

Gram negative diplococci/ kidney bean shaped
Neisseria gonorrhea - have many PMNs
Capnophilic- thrive in high CO2 environment
Growth on routine media
N. gonorroheae- chocolate agar but not blood agar
N. meningitidis- both chocolate agar and blood agar
All oxidase positive
N. gonorrhoeae – glucose only
N. meningitidis – glucose + maltose

56
Q

Neisseria Virulence Factors

A

Pili - attachment to non-cilated epithelial mucosal cells, resist phagocytosis by neutrophils, and antigenic variation to hide from immune system

Por protein:
PorA- silent in N. gonorrhoeae but on in N. meningitidis
PorB- on in both Neisseria gonorrhoeae and meningitidis, must be functionally active, antigenic variation, prevents phagolysosomal fusion

Transferrin-binding proteins (also lactoferrin BPs)- acquisition of iron for growth restricting hosts to humans

LOS- like LPS, but oligosaccharide (shorter); still has Lipid A portion serving as the endotoxin causing pelvic inflammatory disease

IgA protease
Beta lactamase

57
Q

Primary Disease in Neisseria and Epidemiology

A

acute urethritis, proctitis, pharyngitis, ophthalmia neonatorum, acute cervicitis or vulvovaginitis

Epidemiology: US higher than most other developing countries
Poverty, inner city
African-American
Multiple sex partners, recent new partner
females more affected than males; females = reservoir

58
Q

Neisseria gonorrhea: Characteristics

A
  1. Discharge - mucourulent, creamy yellow discharge
  2. Gram stain results – negative in pairs within PMNs
  3. Other tests – NA amplification, oxidase positive, and glucose oxidized
  4. Signs and symptoms & Complications- Sterility from complications

adhere to stratified columnar epithelial cells
penetrate to subepithelial connective tissue and multiply
severe acute inflammatory response

59
Q

Neisseria gonorrhea in Males vs. Females

A

Males: from anterior to posterior urethra and Cowper’s glands; fibrosis - urethral strictures; prostatitis, epididymitis; permanent sterility may develop

Females: burning and frequency of urination, mucopurulent discharge, fever and abdominal pain
from primary foci to fallopian tubes, pelvic peritoneum
salpingitis, tubo-ovarian abcesses,PID
permanent sterility or ectopic pregnancy may result

60
Q

Disseminated Gonococcal Infection - Gonococcemia

A

Sometimes the infection gets into the blood and spreads throughout the body
about 1% of male or female patients, usually w/ asym. genital infection, septicemia
LOS toxicity - chills, fever, malaise, petechial skin lesions
Migratory arthralgia, suppurative arthritis of wrists, knees, ankles, pustular rash on erythematous base on extremities but NOT on head/trunk

Dx: male urethral exudate - gram stain
females - culture and ID
other sites males, females - culture and ID

61
Q

Gonococcemia: Culture

A

inoculate immediately onto appropriate media
Thayer Martin, NYC media
Transgrow, Jembec Plate
does NOT grow on blood agar, only on chocolate
atmosphere (enriched CO2) and temperature important

Nucleic acid amplification assay: test for Gonorrhoea and Chlamydia both
Culture Media: chocolate agar, Thayer-Martin agar, NYC medium
Biochemical testing: glucose oxidized

62
Q

Treatment of N. Gonorrhea and Chlamydia

A

ceftriaxone single dose
treat w/doxcycline for co-infection w/Chlamydia
neonates - drops at birth required by law
0.5% erythromycin
1% tetracycline or
1% silver nitrate (won’t effect Chlamydia)

63
Q

Chlamydia trachomatis

A

obligate intracellular bacterium
cell wall lacks peptidoglycan
life cycle contains elementary bodies, reticulate bodies
require source of ATP from host; will not grow on culture

Elementary Bodies: Infectious form, cannot replicate, bind to receptors on host cells, metabolically inactive

Reticulate Bodies: Metabolically active form, replicating form, non-infectious form

64
Q

Types of Chlamydia

A

Chlamydophila pneumoniae
Chlamydophila psittaci
Chlamydia trachomatis

65
Q

Chlamydia Serovars

A

A, B, Ba, C – Endemic trachoma- eye infection that can lead to blindness is untreated; discharge
B, D-K – Genitourinary disease; discharge
L1, L2, L3 – Lymphogranuloma venereum; ulcerative

66
Q

Chlamydia: General Information

A

Most prevalent STD in US, many are co-infected w/gonorrhea, only source is humans
Other infections: pharyngitis, conjunctivitis, PID (pelvic inflammatory disease), perihepatitis
1. Discharge – scant and watery
2. Gram stain results – PMNs with no gram stain
3. Other tests – NA amplification
4. Signs and symptoms: infection asymptomatic initially
host develops acute inflammatory response - PMN’s
“watery” discharge

67
Q

Urethritis in Men

A

Most are symptomatic
Reiter syndrome: urethritis, conjunctivitis, polyarthritis, mucocutaneous lesions, EB found in specimens with arthritis
caused by chlamydia

68
Q

Pathogenesis of Chlamydia in Males, Females, and Newborns

A

males - disseminate into epididymis - epididymitis
female - travel up fallopian tubes into peritoneal cavity - salpingitis, PID
newborns – mucopurulent conjunctivitis 1-2 wks after delivery; pneumonia, pneumonitis

69
Q

Salpingitis and perihepatitis

A 
Most serious – salpingitis
Range from silent infection to severe 
Fever, lower abdominal pain, tenderness of uterus, adnexae (structures related to the uterus)
Severe inflammatory response
caused by chlamydia
70
Q

Lab Dx: Chlamydia

A

Fluorescent antibody staining of genital specimens, conjunctival scrapings
Culture – most specific and requires tissue culture
can do ELISA, genetic probes
Nucleic acid amplification test

71
Q

Lymphogranuloma venereum

A

caused by Chlamydia trachomatis (not the same as genital chlamydia); L serovars cause
Rare in US, common in developing countries
STD, often co-infection
Would be in differential for ulcer diseases
People who travel out of the country are more likely

Dx: cannot gram stain chlamydia so use NAAT, serology
Isolation of Chlamydia from infected tissues, secretions

72
Q

STDs: Mucupurulent Discharge vs. Ulcerative

A

Ulcerative: Granuloma inguinale, Chancroid, Syphilis, LGV (covered with chlamydia)

Mucopurulent: Chlamydia, Gonorrhea, Trichomonas

73
Q

Painless vs. Painful

A

Painless: Syphilis, LGV, granuloma inguinale,

Painful: Chancroid, HSV

74
Q

Lymphogranuloma venereum (LGV) Stages

A

Primary lesion- generally painless papule that ulcerates, non-indurated herpetiform ulcer

Secondary stage - acute lymphadenitis with bubo formation (painful), acute hemorrhagic proctitis following rectal intercourse, fever, other symptoms of systemic infection

Tertiary stage - rare
Development of genital ulcers, fistulas, rectal strictures, genital elephantiasis – result of inflammatory response

75
Q

Klebsiella granulomatis

A

Disease - Granuloma inguinale aka Donovania granulomatis until recently
Causative agent: gram-negative rod
Pathognomonic feature: Donovan bodies - vacuole w/i PMN or plasma cell where organism multiplies

76
Q

Donovanosis

A

Four classic forms of presentation

1. ulcerogranulomatous
2. hypertrophic or verrucous (cauliflower growth) 
3. necrotic – foul smelling ulcer	
4. sclerotic – formation of fibrous and scar tissue; walled off and thick

Firm subcutaneous nodule progresses to beefy-red, granulomatous heaped ulcer, ulcers generally painless
multiple lesions form; bleed on contact

77
Q

Differential Dx for Granuloma inguinale (Donovania)

A

Carcinoma - esp. with advanced lesions
Syphilis - condylomata lata
Large herpetic ulcers
Amebiasis

78
Q

Haemophilus ducryei

A

Chancroid: aka soft chancre caused by Haemophilus ducreyi; predominantly male disease; has irregular border

Haemophilus ducreyi: gram negative rod with“school of fish” appearance
Reservoir: genital tract of humans
Culture: requires specific media, requires X factor only
Oxidase positive (like gonorrhea and aeruginosa)

79
Q

H. ducryei: Chancroid Pathogenesis

A

Small erythematous papule, not painful initially
Patients seek attention after having ulcers from 3-5 weeks since it is painful at that point
Range from 1-4 ulcers typically
Very painful, friable ulcer with ragged borders develops
Ulcer base may be covered with yellow or grey necrotic purulent exudate
Lymphadenopathy from spread to inguinal lymph nodes
may rupture, exudates highly contagious

80
Q

Dx and Epidemiology: Chancroid/ H. ducryei

A

Definite – isolation of H. ducreyi from lesion
Probable – clinical findings compatible, negative darkfield, negative syphilis serology, negative HSV culture

Epidemiology: Probably underreported, mostly minority populations, African-American, Hispanics, Heterosexuals
Female prostitutes and clients

81
Q

Treponema palllidum: Syphilis

A

Ulcer description: hard chancre, indurated, well circumscribed; painless; regular border

spirochete- thin and cannot gram stain so use silver stain or darkfield microscopy (+ = disease)
corkscrew type motility with axial filaments
Bundles of periplasmic flagella
cannot culture on artificial media
Lack TCA cycle – need host to survive
Sensitive to oxygen

82
Q

Syphilis Transmission

A

sexual contact - abraded skin or mucous membranes
oral, anal sex
congenital
secondary disease w/latent infection

Primary, secondary, tertiary, latent, and neonatal phases

83
Q

Primary Phase of Syphilis

A

Men having sex with other men are at high risk
Located at site of inoculation
3 weeks incubation
Chancre (hard): painless, indurated, well circumscribed ulcer
Regional lymphadenopathy
Heal in 1-6 weeks

84
Q

Secondary Phase of Syphilis

A 
Enter blood from infected foci
Flu-like symptoms
Disseminated rash few days later
Highly infectious
Resolves spontaneously within few weeks
Rash: Unique – found on soles of feet, palms of hands
May be over entire body, in mouth 
Copper penny macules or papules
Resolves on own within a few weeks
Patient has then entered latent stage
85
Q

Secondary Phase of Syphilis Symptoms

A

Generalized lymphadenopathy (large lymph nodes)
Generalized maculopapular rash
Condyloma lata - soft, fleshy papules in genital region
Moth-eaten alopecia (chunks of hair falls out)

86
Q

Latent Phase of Syphilis

A

3 weeks to 3 mos. after secondary stage
Early latent - 1 year duration
Can transmit to fetus
May last 3 to 30 years

87
Q

Tertiary Phase of Syphilis

A

Waning of immunity - w/i mos. to 50 yrs. later
Treponemes invade CNS, CV system, eye, skin, other internal organs
Delayed Type Hypersensitivity reaction or reaction to invasive properties
At this point the organism is no longer responsible, but the immune system attacks
Transmission does not occur
Congenital transmission rare

88
Q

Neurosyphilis

A

Destruction of brain parenchyma (paresis) - dementia
dorsal roots of spinal cord (tabes)
Tabes dorsalis – demyelination of posterior columns of dorsal columns and dorsal roots
or both (taboparesis)
Meningitis – classic aseptic
optic atrophy
meningovascular damage

Cardiovascular Symptoms: thoracic aortic aneurysm
aortitis, aortic endocarditis, on x-ray see ascending aortic calcifications

Skin Manifestations: Gummas =destructive, granulomatous, non-progressive lesions
treponemes rarely found in the lesions
In bones, skin, other tissues

89
Q

AIDS and HIV+ patients: Syphilis

A

higher prevalence of recurrent secondary syphilis

more rapid progression to CNS

90
Q

Congenital Syphilis

A

Sequelae: latent infections, multiorgan malformations, death of fetus
Majority: born without clinical evidence, but shows up shortly after birth

Early (birth to age 2): Extensive cutaneous lesions, rhinitis or “snuffles”, teeth, bone malformations, anemia, hepatosplenomegaly, CNS disease

Late: interstitial keratitis, 8th nerve deafness, notched and spaced incisors (Hutchinsons incisors), “raspberry molars”, sabre shins, saddle nose, cutaneous gummas (granulomas)

91
Q

Lab Dx: Syphilis

A

darkfield microscopy
nontreponemal tests - RPR, VDRL
treponemal test - FTA-ABS, MHA-TP
CSF (acquired and congenital neurosyphilis) -VDRL
increased cell count, elevated total protein

92
Q

Nontreponemal Tests

A

They are general screening procedures for syphilis
RPR (Rapid Plasma Reagin)/circle card test – positive if agglutination; many other things that can give positives; quick and easy to do and cheap
**if positive you would have to confirm them
VDRL – Venereal Disease Research Laboratory: slide flocculation test
Test for cardiolipin- in mitochondrial membrane because the spirochete will destroy cells
IgG or IgM
Some false negative
False positives: autoimmune diseases; Esp. disem. LE
Can use for early syphilis cure following therapy

93
Q

Treponemal Tests

A

for syphilis
Utilize as antigen T. pallidum subsp. pallidum
Fluorescent or microhemagglutination
Measure IgG or IgM
Positive – not an indication of active disease because positive test could signify someone who had the disease in the past
Cannot use to monitor therapy
Specificity 99%
False +: AIDS, HIV+, Pregnant females, Narcotic addicts, Lyme disease, Neonate of infected mother

94
Q

Treatment/Prevention of Syphilis

A 
Penicillin – any stage
IM benzathine penicilllin G
Some recommend 2 or 3 doses 1 week apart
Penicillin allergic – doxycycline or tetracycline
reportable, trace contacts

Microbiology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions